Bentley 4 1/2-Liter “Blower”

Written by Sports Car Market

The 4 1/2-liter Bentley was the last of the traditional big sporting cars with four-cylinder engines. In concept it was a scaled up three-liter with the same bevel-driven overhead-camshaft and non-detachable cylinder head, but output was up to 110-115 bhp and maximum speed to over the 90 mph mark. The supercharged version first seen at the 1929 London show wore its Amherst Villiers blower and twin SU carburetors between the front dumb-irons, and with 182 bhp, speed rose to well over 100 mph, without any loss of flexibility.

The “Blower” Bentley was the idea of Sir Henry Birkin, perhaps the most famous of the “Bentley Boys,” in his quest for more speed and his ultimate aim of winning at Le Mans. Birkin persuaded Bentley Chairman, Woolf Barnato, to employ the engineer Amherst Villiers to supercharge the 4 1/2-liter car, although against the wishes of W.O. Bentley. In order to achieve entry into Le Mans, the Automobile Club de L’Ouest insisted at least 50 Supercharged cars had to be produced for homologation purposes. In total 55 were built, five of which were for Tim Birkin and the remaining 50 were offered to the general public.

The “Blower” Bentleys quickly became a racing legend and their speed, handling and aggressive looks quickly established these rare machines in the history books.

The example discussed here left the works in late 1931 and is recognized by the Bentley Drivers’ Club as a unique example being the only Blower Bentley fitted with a Mayfair Carriage Co. body. The history of ownership is highly comprehensive and well documented.

The first owner in September 1931 was J.R. Quayle who retained the car until 1935 passing to H.ST.M. deTrafford. E.O. Hambleden-Thomas owned it from 1951, passing to I.S. Burge in 1956 and C.B. Seaman in the USA in 1961. In the early 1970s the car returned to the UK and was sold in 1973 through the respected dealer Dan Margulies to C.L. Upjohn, who kept the car until 1977. In the mid-80s another well-known Bentley specialist, Dick Moss, restored the car for its then-owner. Both Dan Margulies and Dick Moss confirm that the original Mayfair coachwork was still fitted, although it had undergone some running repairs during its life. Dick Moss had the coachwork restored, at which time some of the woodwork was replaced. Following this restoration the car won its class at the 1985 BDC Kensington Gardens Concours Event before being shipped to Hong Kong. In 1988 the car returned to the UK again and was acquired by the current owner from Duncan Hamilton.

In the current owner’s enthusiastic ownership the car has been preserved and improved mechanically, and provided its owner with over 35,000 miles of splendid service. Mechanically the car has benefited from a complete overhaul, including the fitting of a counter balanced Phoenix crankshaft and rods. Many years ago the original crankcase was damaged and replaced by another correct Elektron example; the original crankcase is included with the car. The original engine numbers are confirmed on the turret and cam box, as is the original supercharger numbered 136.

It has competed regularly in major historic events and hill climbs such as Nurburgring Old Timer Grand Prix (three times), Shelsey Walsh Hill Climb (won its class), Christie’s Cup at Silverstone (twice), and many more with tremendous success. It was also entered in the Mille Miglia Petro in 1990, covering over 4,000 miles traveling through France, Belgium, Switzerland, Italy and Monte Carlo. This car is most impressive W.O. Bentley and without doubt the fastest and arguably most used original supercharged 4 1/2 litre Bentley to be offered in recent times.

Following a recent test drive the power, speed, and handling of MS 3938 can truly be described as astounding; indeed it is capable of effortless long distance cruising at between 80 and 90 miles per hour.

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